Comparison of the effect of LASIK parameters on the percent tissue altered (1-dimensional metric) versus percent volume altered (3-dimensional metric)
| Autor: | Alain Saad, Perry S. Binder, Damien Gatinel |
|---|---|
| Rok vydání: | 2017 |
| Předmět: |
Materials science
genetic structures medicine.medical_treatment Corneal Stroma Keratomileusis Laser In Situ Visual Acuity Keratomileusis Surgical Flaps 03 medical and health sciences 0302 clinical medicine Corneal edema medicine Myopia Humans 030212 general & internal medicine medicine.diagnostic_test Tissue ablation Volume percent LASIK Corneal Topography Corneal topography Ablation eye diseases Sensory Systems Biomechanical Phenomena Ophthalmology Metric (mathematics) 030221 ophthalmology & optometry Surgery Lasers Excimer sense organs Mathematics Biomedical engineering |
| Zdroj: | Journal of cataract and refractive surgery. 44(7) |
| ISSN: | 1873-4502 |
| Popis: | Purpose To determine the theoretical volumes of flap and tissue ablation altered during laser in situ keratomileusis (LASIK) correction of myopic refractive errors. Setting Rothschild Foundation, Paris, France. Design Experimental study. Methods The theoretical volumes of the flap and ablated corneal lenticules for spherical myopic corrections were calculated by mathematical approximations based on a simplified geometric model. These results were then compared for various zone diameters, dioptric corrections, and the percentage of the volumes altered (PVA) with the percentage of tissue altered (PTA). Results The volume of the flap varied linearly with flap thickness and with the square of the flap diameter. The volume of ablated corneal tissue was estimated to be proportional to the magnitude of myopia treatment and to the 4th power of the treatment diameter. For the same depth of ablation, the volume of tissue ablated can vary significantly, depending on the magnitude of the correction and the optical zone diameter. As a result, the PTA calculation is not predictive of the actual PVA. Conclusions The flap diameters and the laser correction were the most important determinants of the PVA altered during LASIK surgery. New models estimating the volume of the flap and corneal tissue might be necessary to determine their influence on corneal biomechanical stability and each procedure's outcome. |
| Databáze: | OpenAIRE |
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